The Jim Dandy's are cool machines. I've seen alot of them, ebay, other sites, and as far as Iknow you could get a 9 hp briggs or 10hp kohler that early on. Looks like you got the kohler. There are attachments that were made for a lot of things, loaders are definitely an option. As far as frankensteining it, don't go to far, they are worth alot, I saw one that was originally full hydraulic with loader go for,not kidding, $15,000.
It was on ebay. This tractor was completely restored and completely original. I know of quite a few around me including one my buddy's got, has the 9hp briggs tho, Gonna put a 10hp kohler from a case, direct bolt in. Those are nice, fun machines that are really heavy duty. Enjoy it!